To: Teacher2Teacher Public Discussion
I think tangrams are versatile and instructive for children to make and use at almost every grade and level. Since the smallest unit (tan) is 1/16 of the whole, it can help older students to conceptualize proportion and the rudiments of area for triangles, parallelograms, and trapezoids. By 4th grade most students can find the area of squares and rectangles, but they can also begin to translate this knowledge to the other geometric figures the proportional ratio between tans (shapes). Example: Since the smallest triangle is 1/16 of the whole, isn't the area also 1/16 of the whole (original square block)? Even if the algorithms for multiplying fractions have not been addressed, students can still have the opportunity to "discover" possible connections... older students can try to "create an algorithm" that fits their explorations. P.S. I have just graduated from U.W. certification with Masters In Teaching and interned with highly capable students in 4/5 grade (a few of them would love to work like this).
Math Forum Home || The Math Library || Quick Reference || Math Forum Search